| Bull gear - repair or replace
(Jun 11, 2001) |
Bullgear missing teeth! ( SB16)
(Oct 23, 2003) |
| Bull Gear Question. (Aug
19, 2002) |
Bull Gear (Dec 31, 2003) |
| Question about Heavy Ten Bull
Gear (Jan 4, 2003) |
Bull gear replacement
(Mar 27, 2004) |
| 10k Bull Gear Problem
(Jun 29, 2003) |
Bull gear help (Mar 13,
2005) |
| Bull Gear needed (Sep 19,
2003) |
|
| |
| Bull gear - repair or replace |
| My 1945
9" Southbend turns out to have been born a model 'C'. I had the
wrong serial number the first time I called Southbend. I have
started disassembling and cleaning the beast. According to the son
of the (I believe) first owner the lathe hasn't been used for the
last 20 years. The oil has all turned to a nice varnish like coat,
but it is generally cleaning up nicely. The 3 jaw chuck is toast and
a couple of gears have broken teeth. Specifically the bull gear and
the backgear. I recall reading about a procedure for cutting a
groove at the root of a broken tooth and brazing or welding in a new
tooth blank. Has anyone tried this? What are your recommendations
(repair or replace)? Except for the one tooth the bull gear looks
good. The backgear is more questionable it would need several teeth
replaced, but replacement gears seem quite pricey. How can you tell
if the half-nut needs to be replaced? Is it possible to repair a
half-nut? Alan (851) |
| I just recently repaired the back
gear on my 1935 model C lathe. Ordered a new cast iron gear from
McMaster Carr. Chucked the back gear in the South Bend at work and
turned off the broken gear and the shaft so I only took off half the
shaft diameter. then I chucked the gear up and bored it out to about
.001 under the diameter I left the shaft. Applied a little loctite
and pressed it together. Works like a charm so far. Gerald
(852) |
| Could you elaborate
more on what gear you used and how it meshed with the old gears? Did
the new gear have the same number of teeth, pitch diameter and
contact angle? could you provide a part number? any pictures of the
operation? I interpret that the old gear and shaft were integral and
the new one was plain bored. So you turned/faced off the old gear
from the shaft and then put the new one on the old shaft. dennis
(853) |
| Mill a slot, use some Loctite 410
bonder to bond a piece of stock, let it thoroughly cure and then cut
the profile of the tooth. This could be done on the mill if you
grind the profile of the tooth on a HSS tool bit. Make a holder for
your bit, chuck it in the mill or maybe the lathe and cut the
profile of the tooth. I have heard some say they have had good luck
brazing in a piece of stock and then cutting the profile of the
tooth. I've been told by some not to heat the gear, you could
distort it and really ruin it. Because of the angle of pressure and
a good fit of the metal, this repair should last a long time. I
believe the teeth are broken when inexperienced lathe operators try
and engage the backgears without pulling the pin on the bull
gear. Anyway, just an idea for you to ponder. Marty (854) |
| I would think you
would have to have something a lot better than the usual flat belt
drive to break gear teeth by starting up the motor with the
backgears and pin engaged. I manage to do that with embarrassing
frequency and the belt simply jumps off. My guess would be its a
result of hammering on a stuck chuck with the spindle locked in this
fashion. Trying to engage the backgears while the spindle is turning
would do it, too. Anyone willing to admit to having witnessed the
breakage of one of these able to enlighten us? Chris (858) |
| Bull Gear
Question. |
| Is the bull gear
the same for the 9in and the 10K? I don't have a parts catalog. Flash (5876) |
| I can't tell
you if it is or not my parts manual only has the 9" part numbers.
Randy (5879) |
| The part number is *AS1SNK1. The
asterisk and AS means its an assembly, the N means it works on a
Nine inch, the K means it works on a 10K. At least that's the way
others on the list have explained it. Glen (5883) |
| Question about
Heavy Ten Bull Gear |
| I'm
stuck at home with the flu and I can't get to the shop (32 miles
away) to check what is the Diametral Pitch and Pressure Angle for
the Heavy Ten's Bull Gear. I believe the PA is 14 1/2 Deg. but I
can't remember if the DP is 18 or 16? Webb
(8478) |
| If you really
mean the bull gear (at the front of the spindle) it is 14 DP. I
chose to measure the mating gear on the back gear shaft, since it
has fewer teeth, and it is 24 teeth and 1.85" Diam., working out to
14 DP. I also verified that a 16 DP change gear doesn't mate. The
small gear on the other end of the spindle which drives the reverse
gears is 18 DP, and the chain of gears from the stud gear down to
the screw gear on the gearbox input shaft are 16 DP. I don't know
the PA of the bull gear and don't have an easy way to measure it,
but I know the PA on the 16 DP gear train is 14 1/2 Deg., so that
combined with the vintage of these lathes in general make it seem
very likely to me that the bull gear is 14 1/2 Deg. PA as well.
Frank (8479) |
| Frank, yes, I mean the Bull gear. I guess my memory is a
bit faulty when it came to the DP of the Bull gear. Webb
(8483) |
| 10k Bull Gear
Problem |
| I recently acquired
a used '71 10k. Was happily turning away when the lathe screeched
and stalled. The bull gear (with pin out) seems to be semi-seized to
the spindle. The spindle turns fine in direct drive, but with back
gear engaged, I can barely turn the gear (and spindle) with a screw
driver as a pry tool. Despite regular lubrication, it seems to me
that the back gear and/or must have gotten hot and galled. Does
anyone agree/disagree with my diagnosis? If true, it seems to me
that I will have to remove the spindle and resurface/replace the
spindle, back gear, or both.
(12339) |
| The spindle is very
hard, The bull gear is cast. You may have transferred metal from the
bull gear to the spindle. Since this is softer you may be able to
remove it without damaging the spindle. The bull gear may need to be
replaced. You will need to remove the spindle to assess the damages.
Jim B.
(12340) |
| Your diagnosis sounds reasonable, esp. since the
spindle bearings seem fine. Now, for $64k, how does the spindle come
out? I have the parts sheets, which show a split nut on the
left-hand end of the spindle, just to the right of the gears that
drive/are driven by the feed direction control apparatus, but the
threads do not extend to the end of the gear. Is this the key? Or,
do you have suggestions for a source of information on disassembly?
(12342) |
| Remove the locking
split nut. Loosen the bearing cap bolts. Get a large hammer and a
block of wood and drive the spindle towards the tailstock. You can
use the tailstock to help convince the spindle to go back where it
belongs after it is all over. There are spring loaded felts that you
will need to retain with long pins through holes in the headstock
made for this purpose. They are just above the oil gits. Oil comes
out of them when you over fill. While you have it apart, it's a good
time to flush all the crud out of the oil galleries. Kerosene or
something similar works well. When you have it all together fill the
back gear sleeve and spindle sleeve with Teflon grease.
Glen (12344) |
| Before you take out
the spindle do the following. With the pin out of the bull gear does
the belt cone turn free? if so the problem may be in the back gear
assembly. Try turning these by hand. If thy don't turn they have
galled to the eccentric shaft assembly. The bull gear is keyed to
the spindle and cannot gall it. The belt cone is the thing that
turns it may have galled the spindle not the gear. However check the
Back gear assembly first. Jim B.
(12345) |
| Yeah, hope that the
problem is in the back gear shaft, not the spindle/cone pulley.
Damage to the back gear or it's shaft would be much easier to fix.
You should also search for the reason for the seizure: wrong shaft
clearance?, misalignment?, too little tooth clearance? (of course,
that would have been noisy), or in the case of the cone pulley - way
too much belt tension?. You'll probably find a worn and seized back
gear.
(12346) |
| How does the locking split nut come off?
It clearly doesn't unscrew all the way... does it have to be split
some more to clear the gear teeth? Or do I just pull it off (as with
a gear puller) or otherwise pry it over the gear teeth?
(12347) |
| If you are already
sure that the problem is in the cone pulley, and not in the back
gear shaft.... If you want to remove the spindle on a 10K (or 9N): -
Loosen the lock-screw on the spindle endplay take-up nut. Unscrew
the nut. Yes, it should come off of the spindle readily. The nut
should clear the gear teeth which are cut into the spindle. I
suggest that you also remove the feedscrew reversing lever.
Otherwise, it will be a bit in the way. There should not be any need
to pry the slot in the nut (at least not much). - Loosen the
capscrew on each spindle bearing (The 2 big screws in the
headstock). - The spindle can now be driven out of the headstock,
towards the tail end of the lathe. This will require more or less
force, depending on 1) how tight the spindle shoulder is
press-fitted to the bull gear, 2) how much hard, dry oil may be on
the spindle shoulder to the left of the bull gear, and 3) how badly
your cone pulley is seized on your spindle. If it's really stuck,
you may want to use a puller on the cone pulley (w/ the drive screw
on the small end of the spindle).
(12349) |
| James, I have a
1965 10K. Don't get in a hurry on this. If there is ANY metallic
deposit on the spindle just think what bearing damage will be done
when you drive the spindle thru the head stock bearing. There are
procedures on removing the spindle but I too old to recall where I
saw them. Gather info on any set screws on the belt pulley and keys
that are not intended to be driven thru a bearing. Hope this sparks
some thinking and searching. I will check my files on the 10K.
Darrell
(12350) |
| The diameter of the spindle in the
area of the bull gear and the belt cone is quite a bit smaller than
the diameter of the large journal. Removing the spindle will not
damage the bearing. However it might score the come with a lateral
gouge. Jim B.
(12353) |
| In back gear the drive goes: Belt drives pulley running
freely on the spindle (because bull gear pin is disengaged from
pulley), small gear on pulley drives back gear quill running freely
on eccentric shaft, small gear on back gear quill drives bull gear,
bull gear drives spindle through woodruff key. As long as the back
gear actually drives the spindle, even if tight there is drive
between the left gears, between the right gears, and from the bull
gear to thr spindle through the woodruff key. Your tightness appears
to be either the pulley semi-seized to the spindle or the back gear
quill semi-seized to the eccentric shaft. Rotate the eccentric shaft
so that the back gear quill is *disengaged* from the bull gear and
see if the back gear quill rotates freely. If not you appear to have
found the problem. If the back gear quill does rotate freely you
probably have a problem between the pulley bushings and the spindle.
(The above presumes that you haven't tightened the oil hole screws
in the pulley or the back gear quill to the point they are
interfering with the spindle or the eccentric shaft respectively.)
Please let us know what you determine to be the cause. Anthony
(12372) |
| Bull Gear
needed |
| Anyone have a
Bull gear for sale or trade for a heavy 10? Need one from a machine
with the letter 'R' in the serial number. A short time ago there
were lots of headstocks in the junk yard (Ebay) but now its dry.
JP (14069) |
| I have
several heavy 10's that I have parted out and am not aware of the
bull gears being different. What is different on the "R" model from
the rest? Maybe someone can enlighten me on this. I guess I really
never paid that much attention. If you can supply me with some more
info, number of teeth, bore size and width of the gear, I might be
able to help you locate one. What do you have for trade? My guess
is, I have at least two heavy 10 bull gears, along with allot of
other pieces here that I will not be using anytime soon. I am
currently arranging these lathes for restoring, (7 at the moment)
Randy (14073) |
| All
heavy 10's have an R as the 1st letter in the serial number. This
includes both the early heavy 10 "regular", or 10R, lathes with
small spindle bores (model numbers based on 199) and the much more
common (at least in later years) "large spindle bore" heavy 10, also
known as the 10L, whose model numbers are based on 187. The 10"
lathes whose serial number letters begin with a K are so-called 10K
or light 10 lathes. The part number for the heavy 10" bull gear has
an R in it, indicating that it is the same part for the early 10R
heavy 10" lathes as the later 10L. Parts which SB had to change for
the 10L based on the large spindle bore have an L in them instead of
the R. I would bet that any heavy 10" bull gear will fit any heavy
10" lathe. Frank (14079) |
| Oops- I should have
said: "All heavy 10's built after the 1947 change in serial
numbering have an R as the 1st letter." I was referring to JPs lathe
(made circa 1959 as I understand it) in the comment, but realized I
may have confused those with older heavy 10's. Frank (14082) |
| This is what Roger
at Leblond told me, I think it just means heavy 10 or Model CL187.
The gear is 75 tooth, 14DP, 5.5"OD and 5/8" face width. The spindle
has a 1 3/8" bore and 5MT taper in the front and 2 1/4" threaded
spindle nose. John (14099) |
| Bullgear
missing teeth!( SB16) |
| I took off the covers from the bullgear, and found several
teeth missing Oh No!!!! I was wondering with the covers removed
and I can see the gears. Should I be able to turn the bullgear
independently of the cone pulleys? No matter what position the
button is in up or down I can't turn these pulleys separately. Is this
normal? What actually happens when this pin is pulled out or moved up
or down? Does anyone have an exploded parts view of the head that
they could email me? I don't understand exactly how the back
gears change the speed right now I see through the glass darkly.
(14583) |
| I would say the 16"
is pretty much the same as most SBL's if you pull the pin the pulley
should be free. there may be jelled oil in the pulley that has
frozen it to the spindle. I ran into a similar problem when I bought
my 10L SBL. it had at least 3 teeth missing. I was lucky and had an
extra 3jaw laying around and I traded it for a good bull gear. I
would say the head is similar to my 10L SBL if you want a scan of my
10L head diagram i could scan it. Kevin W (14584) |
| I don't
understand what you mean "button up or down" you need to pull the
button or plunger out to disengage the bull gear. With the plunger
out and the back gears NOT engaged the bull gear should turn free. I
am assuming SB 9 or 10L when I say this. Bull gears show up
frequently on E-Bay Jim B. (14587) |
| It sounds like the
cone pulley is stuck to the spindle. There should be oil fill screws
on the cone pulley. You can use penetrating oil in there and try to
free it with the pin out on the bull gear. I use 'Break Free with
CLP', it will free up most anything, mystery oil might work. It may
take a few applications and some time. The cone pulley rides on the
spindle independent of the bull gear. CE3458 parts manual from
LeBlond is what you need. The bull gear is pressed and keyed to the
spindle independent of the cone pulley with the pin out and locked
to the pulley with the pin pushed in. Mine was broken and 'repaired'
by someone who pressed pins into the tooth locations and filed the
ends to the involute shape. I would recommend finding a used good
bull gear from the same size machine and replacing yours. The bull
gear is used with the back gear assembly to generate the low speeds.
JP(14589) |
| Sounds
like an older model lathe. On my SB13 ('31) the button pulls out
then slides down to release the pulley and small spindle gear from
the spindle. The large (inboard) gear on the spindle is fixed to the
spindle. When you release the spindle pulley / small gear from the
spindle, you should be able to turn the cone pulley without the
spindle turning (other than by drag). Once this happens, you can
bring the back gears into place. The small spindle gear (loose from
the spindle, remains connected to the cone pulley) drives the large
back gear giving the first speed reduction. The small back gear
drives the fixed spindle gear, giving another reduction. The cone
pulley spins at normal speed, the back gear assembly spins at a
lower rate, and the spindle in turn spins at a rate slower than the
back gear shaft. Neat little arrangement. The button is connected to
a plate mounted on the rear side of the fixed large spindle gear so
it can slide up and down (towards/away from the spindle.) This
locking plate seats in a slot inside the large end of the cone
pulley when in normal mode, locking the cone pulley to the spindle.
The pin secures the locking plate at either end of it's motion. To
fix missing gear teeth, you can: Drill and tap holes of appropriate
size at the root of the broken tooth, then thread in bits of drill
rod or setscrews. File/grind to match profile. You could skip the
drill and tap, and simply press in pins. You can also make the hole
a thou larger than the pins and use LockTite bearing retaining
compound. 660 is quite strong stuff, just don't dawdle while tapping
the pins home, it sets fast. A nicer fix is to do the above but fill
the area with braze, then file/gearcut the profile. Don't go the
bearing retaining compound route if you do this, Locktite breaks
down well below brazing heat. If you have a mill or shaper, you can
cut a slot at the root of the missing tooth, and silver solder/braze
in replacement cast iron teeth. You can form the tooth profile on
the replacement teeth before silver soldering them in, making the
final cleanup and shaping a quick job with a die grinder or Dremmel
tool. I use old cast iron Emglo compressor valve plates, and saw off
small rectangles a bit oversize size then file or grind them to
profile and a nice fit in the slot. If you go this route, you can
use a silver bearing solder rather than true silver solder (really
silver braze), which melts at a lower temp. Makes the preheating of
the entire gear less of an issue, a pair of propane torches will
work for this approach, so you don't need an O/A rig. I fixed a few
missing teeth on my lathe back gears this way, works fine and you
have to look closely, knowing the repair was done, to find them. I
suppose you could use bearing retaining compound here, or a tapered
dovetail press fit plus retaining compound if you want to avoid
torch work. All of the above work well, it's just a matter of what
other machines you have available and how far you want to go to
restore the missing teeth. Once done, get in the habit of engaging
back gears ONLY after releasing the spindle lock, and disengaging
them before locking the spindle. Most broken back gear teeth are
caused by someone either engaging the motor with the spindle locked,
or more often intentionally locking the spindle by engaging the
backgear with the spindle cone pulley locked and trying the break
loose a badly stuck chuck. It's OK to lock the spindle this way to
remove a chuck that's just on the lathe normally, but not for
getting a badly jammed chuck off. You might search the message
archives for gear teeth, broken teeth, and stuck chucks. We've had
quite a few threads related to this subject, you can find lots of
alternatives and opinions. Most of the folks that restore old
machines run into these issues, you're not alone!
Stan (14596) |
| I have color photos of the parts in question. One pic is of the
backside of the spindle, you can see the sliding bar. Next is a shot
of the inside of the step pulley, you can see two of the slots that
the sliding bar engage. Obviously only one slot is used at a time.
http://photos.groups.yahoo.com/group/southbendlatherestoration Michael (14609) |
| Bull Gear |
| Does anybody know
where I can get a spring and plunger for the bull gear on a SB 10
Heavy. Vinny (16097) |
| I have a full heavy
10 in parts on ebay now. Yes I offered it all here 1st! Jeff (16098) |
| If you are talking
about the pin you push in and out to put the machine in back gear? I
found them at LeBlond but the pin was almost 50 and the spring was
reasonable at about 7.00 . I made a pin in about 15 min out of drill
rod and hardened it , works fine. I have the measurements if you
need them let me know. Grumpy (16099) |
| I found them at
LeBlond but the pin was almost 50 and the spring was reasonable at
about 7.00 . I made a pin in about 15 min out of drill rod and
hardened it , works fine. I have the measurements if you need them
let me know. Grumpy: I would more than appreciate the measurements
for the pin. I'll call LeBlond next year. Vinny (16100) |
| You can
make the spring from a few inches of music wire bent in a 'U' shape.
JP machine in the spring drill rod them let pin. (16102) |
| Bull gear
replacement |
| I need to replace
the bull gear on my 9"sb. lathe. I am kinda at a loss as to how to
take the head stock apart. An exploded view, break down would help
out a lot. Where could I get something like this? (18021) |
| Go to:
http://metalworking.com/DropBox/_2001_retired_files/sbarmylathe.pdf
This is a big file. 1.3 megs. If you are on dial up it will take a
while. This gives breakdowns on all assemblies and is referred to as
the "Army Lathe Manual" Jim B. (18023) |
| Bull gear help |
| In a short time I
will be given an old Clausing bench lathe that has a capacity of 12"
swing with 24" between centers. It is in pieces and needs TLC.
Somebody took it apart, never put it back together, and gave it to a
friend of mine, in pieces. He has a larger Hendey lathe, and
therefore, out of the blue, asked me if I wanted it. This is a
Clausing rather than a Atlas because it has V-ways. I believe it is
a Clausing 100, or when Atlas bought Clausing, an Atlas 4800. I
believe it has a full QCGB and power apron. It needs new spindle
bearings, cross feed nut and a Bull gear. It is also missing it's
countershaft assembly. The bull gear is completely missing. To fix
it, I'm considering buying a spur gear from MSC, and boring it out
to fit the spindle. Since the pin of the bull gear must be fairly
secure, and most gears of this diameter have spokes, How would I go
about doing this. I recall an article in HSM about doing this for a
Southbend, but do not have the article. Does anybody have this
article? I would like to do the same procedure on this Clausing when
it comes in. Has anybody in this group bought an off-the shelf
Boston gear and replaced their bull gear? Aside from boring the gear
to fit, what else needed to be done? Gabe (26025) |
| I have a Series 100
Mk 3A 12 x 36. I was able to get a manual from Clausing Service
Center in South Bend, but so far, no parts. Then manual has a fairly
good breakdown of all the parts. Be sure to include the serial
number from the tailstock end of the bed. I think shipping and al
was about eighteen bucks. I needed some clutch and brake parts for
the countershaft, but they were unavailable so I made them. the rest
of the lathe is in phenomenal shape and is a peach to run. I can
probably come up with pictures and measurements if you need them.
Jeff (26054) |
